Abstract
Measurements of the electrical resistivity and thermoelectric power for sintered samples of K0.2Ba0.7Y0.3CuOx system were carried out. Two sets of the samples were prepared, the first set was sintered in air and the second set was sintered during flowing oxygen. The temperature dependence of the resistivity was found to be similar to that of metals. Further, the zero resistance was attained at 91-95 K depending on the sintering time. The author believes that, the prolonged sintering time caused oxygen vacancies (which may reside either along central-cage Cu-O chains) to become positively charged on trapping the hole, and thus enhance the superconductivity. The thermoelectric power of all samples was found to possess plus sign and decreases slightly with decreasing temperature, and then it falls down to zero, at the critical temperature (T-c).